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Calculate SAC (surface air consumption)

I have an important suggestion:
Enter information about the diving SAC (surface air consumption).
This is important to know how is our consumption of air.
It is necessary to calculate the following information:
D=Average depth(m); V=Cylinder Volume(liter); T=time depth (min); P=pressure consumed(bar).
SAC (L/min)= (P x V) / ((1+D/10) x T)
more information in english: http://www.dive-logs.com/infosac.jsp?BaseFontSize=15